Seal for rotary regenerator



Dec. 22, 1964 R. SMITH SEAL FOR ROTARY REGENERATOR 4 Sheets-Sheet 1Filed Oct. 25, 1961 mvamolp Raymond Jm/fh AYTORIVEYS Dec. 22, 1964 SMITH3,162,241

SEAL FOR ROTARY REGENERATOR Filed Oct. 25, 1961 4 Sheets-Sheet 2INVENTOR.

Raymond fimhh Dec. 22, 1964- R. SMITH SEAL FOR ROTARY REGENERATOR 4Sheets-Sheet 3 Filed Oct. 25, 1961 Dec. 22, 1964 SMITH SEAL FOR ROTARYREGENERATOR 4 Sheets-Sheet 4 Filed Oct. 25, 1961 w aw 9v 9w A ww mm QM.3 iv v fi u mrnm i mm: m3 3 m a xy/ kmf L 4/ /7 m. mmM/11\ i A mmmwfivbk m b {v the matrix in the colder stages.

United States Patent Ofilice 3,152,241 Patented Dec. 22, 1964 3,162,241SEAL FOR ROTARY REGENERATOR Raymond Smith, Fraser, Mich, assignor toContinental Aviation and Engineering Corporation, Detroit, Mich, acorporation of Virginia Filed Oct. 25, 1961, Ser. No. 147,512 Claims.(Cl. 165-9) This invention relates to heat exchangers and particularlyto improved sealing means for a rotary regenerative type heat exchanger.

In a preferred rotary heat exchanger of the type used in turbineengines, an annular framework carrying a matrix of heat absorbentmaterial rotates in a stationary casing. The matrix may be a drum-likeannulus or a series of discs. In any event, the casing is dividedradially into two sections which are, as far as possible, sealed fromone another. The hot exhaust gases are directed into one of thesesections and the cold compressed air is detoured through the other onits way to the combustion chamber. The matrix rotates in the paths offlow of both of these; the effect being that a large amount of heat fromthe exhaust gases is transferred to the compressed air. In this way,energy in the form of heat which would otherwise be lost is retained inthe engine.

Efiiciency is lost in such a heat exchanger unless an effective seal isprovided between the casing and the rotating matrix to minimize theintermixing of the air and the exhaust gases. Since the air has beencompressed a pressure drop resulting from leakage of the air into thelower pressure exhaust represents a direct loss of the energy producedin compressing.

Such a seal must be constructed in a manner which will compensate forthe distortion and warping which occurs due to the fact that thedifferent parts of the apparatus are subjected to varying as well asintense heats during operation. Further, the seal should be constructedso that the effect of friction is minimized.

In an exchanger employing a drum matrix as discussed herein, the pathsof flow of the hot gases is generally radially outwardly through thematrix. The cold air, on the other hand, flows radially inwardly throughthe matrix. The inner ring of the matrix then receives the hot gases aswell as the heated air while the outside ring receives the cold air asWell as the gases after the heat has been substantially removed. Thesepaths of flow then produce a hot ring and a cold ring, producing adistortion or warping in the form of an expanded inner ring. Any sealutilized must take into consideration this fact and therefor mustinclude some thermal compensating means to overcome it.

Heretofore, attempts at providing a seal for this type of heat exchangerhave not been too successful. Generally, these seals have consisted of aflexible seal projecting from the casing in contact with and acting towipe the rotating matrix. During operation, the distortion and warpingdescribed above tends to separate the matrix and-casing more and more asthe apparatus gets hotter and hotter. Thus such a seal, to be effectivein the hot stages or operation, must bear too hard against Energysavedby an effective seal while the apparatus is hot is lost throughincreased friction while the regenerator is cold.

" '-An object of the present invention is to provide a novel seal whicheffectively separates the exhaust gases and air at all stages ofoperation through the provision of v a thermal compensating structure.

the air and gases from each other at all times during operation.

Still another object is to provide an effective sealing means whichminimizes friction at all times during operation by utilizing a rollingseal.

Other objects of the invention will readily occur to those skilled inthe art upon reference to the accompanying drawings showing a preferredembodiment of the present invention in which like characters refer tolike parts throughout the several views and in which FIG. 1 is aperspective diagrammatic view of a structure embodying the presentinvention from which parts of the assembly immaterial to theunderstanding of the invention have been omitted.

FIG. 2 is a cross-sectional view of a rotary regenerator embodying thepresent invention taken substantially on the line 2-2 of FIG. 3.

FIG. 3 is a cross-sectional view taken substantially on line 3-3 of FIG.2.

FIG. 4 is a longitudinal cross sectional view of a roller embodying theinvention and,

FIG. 5 is a cross sectional view taken substantially on line 55 of FIG.4.

Referring first to FIG. 1 for a general description of the regenerator,it comprises an annular matrix 10 in the form of a drum, the edges ofthe drum being defined by end rings 11 capped by annular retainers 12Aand 12B. Gear teeth 13 are provided on the outer peripheral edge of oneof the annular retainers 12A. The heat exchange portion 14 of the matrix10 is fixed between the end rings 11 and may be of any suitable heatabsorbent material known in the art such as thin corrugated sheets ofmetal. A bulkhead assembly 15 divides the regenerator into two sections.The regenerator housing and other structures by which the air and gasflow is directed have been omitted from FIG. 1 in order to more clearilyillustrate the general arrangement of a regenerator embodying thepresent invention.

Referring now to FIGS. 2 and 3 for a more detailed description of theapparatus embodying the present invention, a casing 16 cooperates withthe bulkhead assembly 15 and duct work (not shown) to form passagewayswhich direct the flow of gas and air through the regenerator. Asindicated by the arrows at A in FIG. 2, air discharged from a compressor(not shown) fiows radially inwardly through the heat exchange material14 and leaves the regenerator axially. Exhaust gases, as indicated bythe arrows at B, are discharged from a turbine (not shown) and enter theregenerator axially, flowing radially outwardly through the material 14.

The casing 16 rotatably carries a drive shaft 17 by any means such as apair of bearings 18. An extended portion 17A of the drive shaft 17 maybe connected to any convenient driving means such as a turbine (notshown). The drive shaft 17 extends through a spacer tube 19 which fixesin spaced relation a pair of friction rings 20. A jam nut 21 cooperateswith an annular boss 22 in the drive shaft 17 to secure the frictionrings 20 and the spacer tube 19 to the shaft 17. The rings 20 and tube19 may be prevented from rotating relative to the shaft 17 by anyconvenient means such as a key 23.

The bulkhead assembly 15 comprises a substantially convex partitionplate 24 carrying a cylindrical housing 25 at a pair of opposite edgesby any convenient means such as bolts 26. The housings 25 are adapted toenclose a roller assembly 27 to be described more fully below. Alongitudinal sector is removed from each cylindrical housing 25 forminga slotted portion 28 exposing the roller assembly 27 to the innerlateral wall of the matrix 11). The partition plate 24 is secured to thecasing 16 by any convenient means such as bolts 29.-

Cylindrical housings 15A, similar to the housings but preferablysomewhat larger, are secured to the casing 16 by anyconvenient meanssuch as bolts These too are constructed to enclose a roller assembly 275like roller assembly 27 but again somewhat larger. slot 28A provided inthe housing 25Av exposes each roller assembly 27A to the outerperipheral wall of the matrix I V a 4 heretofore friction had to begreat ia cafififi'sate far the warping present in the hotter stages. a

It will be apparent, to those skilled in the art from the foregoingdescription that'thethermal compensatingv seal of the present inventionis highly advantageousirr reducing leakage and friction in'rotaryregenerators andvthereby increasing; the efi'iciency', of fmachineslinwhich it is in substantial alignment with, the slot 28 provided in ofthis assembly with respect Ito the othei'paits of he regenerator. N U hH ably secured to the casing-t 'l fi by any convenient means such asbearing assemblies 35 carried A geared ring 37 is positioned on theshafts to 'n'ish with the gear teeth 13 provided oh the matrix 10' bymeans of a spacertube SS 339 are posed on the shaft 34 between thespacer tube}? and a second spacer tube 38A,; cap element acting with thespacer tube and the spaeer tube 38Apositions the annular spacer elementssubstantially in alignment with thelateral edge of the 10. This assemblymay be fixed to the drive shaft 314 by any means which prevents relativerotation such as a'key' 41.

plurality ofi annularly spaced radially eXteiiding slots 42 as best seenEach o i these is de signed to take a vane assembly 43.

annular grooves d8projvided each ende f thespecer The assembly 2ezsinsases a shaft 34 m t} 53 apjscrews 36.;

Each of the spacer elements fi isjp rovidedwith a c employed. Thesimplicity'of structure which the present invention enablesis also animportantfadvantage.

It will also be apparent to those skilled in the art that 1 while onlyone preferred form of the invention hasbeen elements 39. Rings 49retainedin the groo'yes of I adjacent spacer entrants 39 pass thi' oughthe slots and to retain the individual vane seals 46 in the slots 42; vV

Each; of the roller assemblies 27 and 2 7A a're construct'edsubstantially in the; manner, described above;

except that theassernbly 27A is preferably larger as heretoforeindicated;

In operation the friction rings 20 frictionall'y contact the end rings11 to rot-atablydrive the. matrix 1 0,lal-

though it is apparent that any one or more ofthe rciller v assemblies 27and 27A; could be drivin-gly connected to a V y source of power and usedto rotate the matrix 10 without. I theneed forthe friction ringsZO. Thisrotationaliforceis transmitted to the roller assemblies 27 and 27A bythe geared retainer 12A and the geared rings 37. The springs which willtake place in the as therege'neratorf V jecomesh'eated. The wavespring'di is designedto'fapply I tension to each individual vane element46.; enabling it to extend or retract Where warping oridistorti'onoccurs.

friction especiallyin the colder stages offopera'tionwhe e 44 and'ASnrgethe vane as'sernbliesAB into rolling con f The rings49 bind the vaneseals 46'together sufiiciently;

:tomaintain a line contact with the, niatrix l ti at all tiniest f 1 vThe rolling contactoffthe seals'ininimizes' theaeifect of a illustratedand described} various changes and 'rr'iodifiatio'ns in constniction maybe hadWithout-departing froth the spirit of the invention or near thescope of the appended claims.

lclaiffii 1'. In regenerative heat ieliaiig apparatus i) a g, f f .m 5 amatrix ofheat absorbeht material ro'tat'ably carried at said arising; r1

fans for partiti'onifigsaid easing into at least two 7 sect1oiis,-

'- (d) rollers rotatabiy carried in said easing inte'inidiate v saidseetibns;

(a) aaiagzmeaas disposed at and series in sailing eoii'taetwithsaidmitt-iii, (ff cnqf said rollers comprising," 7 I a shaftrotatablysecured to said easing,

a spacer tube carr ied ateachend of said shaft; aplu'rality of axiallyaligned taniiillarspacer a6, merits disposed between said 'spa'ceitubesadd 7 i fiiced to'said shaft torrdtatidii therewith, Y theeiids of; saidspacer elements being ismidea y w in-any aligiied annular grooves, v I'retai'niiig "rifig's c ed in "aid annular gr do'v'e's ofadjacentspaereleiiieiits aiid v v saidfspacer ele'in nts being providedwith a plufalityof a lig dnar'iiiul aily' spaced radially eit- I tendingslots, afid- (a) said sealing means being cairiea in said slots and eachof said sealiil'g means comprising a pl'ufality of s'r'ib'st'initiallyrectangular.- vane eleriiefits car'rie'd in each of said slots,

"vane ele'iiieiits' in registry with said grooves pro- 7 iiitled in saidspacf element s, v said 'rtairierrin'g s being reeeived by said vanee'lenierit grooves whereby'said vane elements are retained in saidslots, and v means urging each of said vane elements outwardly wherebysaid individual vane elements will be urged into ebritactwith saidmatrix and said re- 1 taiiiing rings will bind; adjacent vane'elemeiitstogeth'rfisufi'ieieh tlyto maintain a line contact witli'said'matrixi" Ia 2. In a regenerative heat exchange apparatus I v (a) a casing.

'a 'matrix of "Bear absorbent material rotatably' carriedin said-casing,Y ,t (0) means for partitioning said casing into at leastitwo section's,V v a 1 (a!) rollersrotatably carried in said casing-intermediate 7 saidsections,; (e) se'aling means contact with said matriir,

dispos d insaid rollers in sealing 10?) @5611" said rollersbeingprovided plurality:

' of annularlyfspacd;radiallyjextending slots and aj Of axiallispaced aXiallYi aligned retainer rings passin'g th'rough 's 1d slots", g 3

5(3) s'a'id' sealing rnean's being" Carrie insaid slots and.

' e'achjofsai d sealing means cornpi ising a pluralit miles I greet/{esbeing proviae'a in the lateral edges or said y ofv he elements carriedin each ofsaid V a 'ai' it h n t dges" extending radiallywith-fres'peetttof said.

grooves being provided in said edges and receiving said retainer ringswhereby said vane elements are retained in said slots, and

means carried in said slots and urging said vane elements radiallyoutwardly.

3. In a regenerative heat exchange apparatus (a) a casing,

(b) an annular matrix rotatably carried in said casing and having innerand outer peripheral walls,

(c) means for rotating said matrix,

(0.) a partition plate secured to said casing dividing said easing intotwo sections,

(e) substantially cylindrical housings carried at op posite edges ofsaid partition plate and each of said cylindrical housings beingprovided with an elongated radially extending slot disposed closelyadjacent said inner peripheral wall of said matrix,

(f) a roller member rotatably secured to said casing and carried in eachof said housings,

(g) each of said roller members being provided with a plurality ofradially extending annularly spaced slots,

(/1) a vane assembly carried in each of said roller member slots,

(i) each of said vane assemblies comprising a plurality of vaneelements, retaining means carried by said roller member and resilientlysecuring adjacent vane elements one to the other and means resilientlyurging said vane elements radially outwardly.

4. The heat exchanger apparatus as defined in claim 3 and in which saidretaining means comprises a plurality of retainer rings, said Vaneelements being substantially rectangular, slots being provided in thelateral edges of said vane elements, and said retaining rings passingthrough the slots of adjacent vane elements whereby to allow each ofsaid vane elements to be independently urged by said urging means Whileat the same time maintaining substantial line contact between said vaneelements and said matrix.

5. The heat exchanger apparatus as defined in claim 3 and in which saidurging means comprises a wave spring and a seat spring, said springsbeing disposed in said roller whereby said wave spring acts to urge eachof said vane elements outwardly.

6. The heat exchanger apparatus as defined in claim 3 and in which saidrotating means comprises a drive shaft adapted for connection with asource of power, said drive shaft being rotatably carried in saidcasing, friction rings carried in spaced relation on said drive shaft,means for preventing relative rotational movement between said driveshaft and said friction rings, said matrix comprising a pair of annularretainers, said friction rings being disposed in frictional contact withsaid annular retainers whereby r0- tational force applied to said driveshaft is transmitted to said matrix.

7. In a heat exchanger apparatus having a casing providing at least twosections and a matrix rotating in said sections, a sealing meansengaging said matrix to seal one section from the other and comprising(a) a roller adapted to be rotatably carried in said casing closelyadjacent said matrix,

(b) said roller being provided with a plurality of annularly spacedradially extending slots,

(0) a plurality of vane elements carried in each of said slots,

(d retaining means carried by said roller and resiliently securingadjacent vane elements one to the other, and

(e) means resiliently urging said vane elements radially outwardly intocontact with said matrix.

8. The sealing means as defined in claim 7 and in which said retainingmeans comprises (a) a plurality of axially spaced rings carried by saidroller,

(b) slots being provided on the adjacent edges of each pair of said vaneelements, and

(c) each of said slots of adjacent vane elements receiving one of saidrings.

9. The sealing means as defined in claim 7 and in which said rollercomprises (a) a plurality of axially aligned annular spacer elements,

(b) said slots being provided in said spacer elements.

10. The sealing means as defined in claim 9 and in which said retainingmeans comprises (a) a plurality of axially spaced rings carried by saidannular spacer elements,

(b) slots being provided on the adjacent edges of each pair of adjacentvane elements,

(6) each of said slots of adjacent vane elements receiving one of saidrings.

References Cited in the file of this patent UNITED STATES PATENTS1,603,437 Winquist Oct. 19, 1926 1,964,492 Yandell June 26, 19342,915,297 Lange Dec. 1, 1959 3,057,604 Bubniak et a1. Oct. 9, 1962

7. IN A HEAT EXCHANGER APPARATUS HAVING A CASING PROVIDING AT LEAST TWOSECTIONS AND A MATRIX ROTATING IN SAID SECTIONS, A SEALING MEANSENGAGING SAID MATRIX TO SEAL ONE SECTION FROM THE OTHER AND COMPRISING(A) A ROLLER ADAPTED TO BE ROTATABLY CARRIED IN SAID CASING CLOSELYADJACENT SAID MATRIX, (B) SAID ROLLER BEING PROVIDED WITH A PLURALITY OFANNULARLY SPACED RADIALLY EXTENDING SLOTS, (C) A PLURALITY OF VANEELEMENTS CARRIED IN EACH OF SAID SLOTS, (D) RETAINING MEANS CARRIED BYSAID ROLLER AND RESILIENTLY SECURING ADJACENT VANE ELEMENTS ONE TO THEOTHER,AND (E) MEANS RESILIENTLY URGING SAID VANE ELEMENTS RADIALLYOUTWARDLY INTO CONTACT WITH SAID MATRIX.